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The aim of the article was to compare the conditions of silent and contralateral noise on Differential sensitivity in normal hearing individuals. A total of 40 participants (20 males and 20 females) were enrolled in the study with a mean age of 21.7 years, participants with normal hearing thresholds and no history of middle ear pathology were enrolled for the study. Difference limen tests such as difference limen for intensity (DLI), difference limen for frequency (DLF), and difference limen for time (DLT) were carried out in these 40 individuals in the two conditions of silent and contralateral noise using MATLAB. Statistical analysis was carried out using the SPSS version 25.0 were descriptive and inferential statistics were carried out. Data was normally distributed on the Shapiro–Wilk’s test of normality due to which a paired t test was carried out to establish the nature of significance between the silent and contralateral noise condition. Results reveal the presence of significant difference (P

Funder: Norges Teknisk-Naturvitenskapelige Universitet; doi: http://dx.doi.org/10.13039/100009123, Funder: Molde University College, Funder: Molde University College - Specialized University in Logistics, INTRODUCTION: Maximal strength training (MST), performed with heavy loads (~ 90% of one repetition maximum; 1RM) and few repetitions, yields large improvements in efferent neural drive, skeletal muscle force production, and skeletal muscle efficiency. However, it is elusive whether neural adaptations following such high intensity strength training may be accompanied by alterations in energy-demanding muscular factors. METHODS: Sixteen healthy young males (24 ± 4 years) were randomized to MST 3 times per week for 8 weeks (n = 8), or a control group (CG; n = 8). Measurements included 1RM and rate of force development (RFD), and evoked potentials recordings (V-wave and H-reflex normalized to M-wave (M) in the soleus muscle) applied to assess efferent neural drive to maximally contracting skeletal muscle. Biopsies were obtained from vastus lateralis and analyzed by western blots and real-time PCR to investigate the relative protein expression and mRNA expression of Sarcoplasmic Reticulum Ca2+ ATPase (SERCA) 1 and SERCA2. RESULTS: Significant improvements in 1RM (17 ± 9%; p < 0.001) and early (0-100 ms), late (0-200 ms) and maximal RFD (31-53%; p < 0.01) were observed after MST, accompanied by increased maximal Vmax/Msup-ratio (9 ± 14%; p = 0.046), with no change in H-reflex to M-wave ratio. No changes were observed in the CG. No pre- to post-training differences were found in mRNA or protein expressions of SERCA1 and SERCA2 in either group. CONCLUSION: MST increased efferent neural drive to maximally contracting skeletal muscle, causing improved force production. No change was observed in SERCA expression, indicating that responses to high intensity strength training may predominantly be governed by neural adaptations.

Introduction Distortion product otoacoustic emissions (DPOAE) and their suppression may be considered useful in monitoring cochlear function and the efferent auditory pathway inhibitory effect. Nonetheless, the establishment of reliable parameters of response variations is of great importance. Objectives To verify the replicability of test and retest in the research of the inhibitory effect of the efferent pathway using contralateral suppressing stimulus during DPOAE recording for clinical applicability. Methods Cross-sectional study with 48 volunteers, aged 18 to 30 years, with normal audiometric thresholds. The procedures included were audiometric and immittance measures to overrule any conductive or sensorineural conditions and DPOAE recordings without and with contralateral suppression with a 60 dBHL white noise. Distortion product otoacoustic emissions amplitudes were analyzed and compared in both conditions with Wilcoxon test, and the Spearman correlation test was used to assess test-retest reliability. Results The comparative analysis showed differences between amplitudes in test and retest conditions only in 1,500 Hz for DPOAE measures with all other tested frequencies showing no differences, and no difference was observed in all recorded frequencies in the test and retest comparison for DPOAE suppression. The degree of correlation between test and retest of DPOAE amplitude was good at 6,000 Hz and strong (r > 0.880) at the other frequencies. For DPOAE with suppression, all frequencies presented strong correlation between test and retest: 1,500 Hz (r = 0.880), 2,000 Hz (r = 0.882), 3,000 Hz (r = 0.940), and 6,000 Hz (r = 0.957). Conclusions The study found good replicability in contralateral suppression of DPOAE with potential clinical applicability, and we recommend conducting the test from 2000Hz to higher frequencies for more reliable results.

Cervical myofascial pain syndrome with dizziness (CMPS-D) has always faced the challenges of evaluation, diagnosis, and etiology. Vestibular-evoked myogenic potentials (VEMPs) are applicable to evaluate the functions of the vestibular system, especially the saccule. The Sound evoked triceps myogenic potentials (SETMPs) have different anatomical efferent connections from Sternocleidomastoid (SCM)-VEMPs. The present study aimed to evaluate the SETMPs and SCMVEMPs in CMPS-D group and compare the results with the control group. We tested 15 participants with CMPS-D with 15 participants in the control group using SCMVEMP and SETMP tests. All participants had normal hearing and vestibular functions. The SCMVEMP response was absent in 4 of 15 patients with CMPS-D, and the mean response CMPS-D group was significantly lower than the control group. There were the SETMP and SCMVEMP responses in all participants in the control group. In CMPS-D subjects with false absent SCMVEMP response, SETMP tests are suitable alternatives for the saccule evaluation, and diminished SCMVEMP in the CMPS-D subjects may not necessarily mean the saccular injury. Furthermore, the involvement of spinal cord pathways is not a cause of dizziness in CMPS-D patients.

Purpose To investigate the dilated choroidal veins (DCVs) at or around myopic macular neovascularizations (MNVs) and to determine whether there is a hemodynamic relationship between them. Methods Fifty-eight eyes of 57 patients with myopic MNVs were examined. Dilated choroidal veins were defined as choroidal veins whose diameter was 2X larger than adjacent veins. Indocyanine green angiography and swept-source optical coherence tomography images were reviewed to detect DCVs that crossed the subfoveal area. The filling sequence of the DCVs and MNVs was determined. Results Patients' mean age was 71.4 ± 10.6 years. The mean axial length was 29.3 ± 1.8 mm. Dilated choroidal veins below or around the MNV were found in 17 eyes (29.3%). Emissaries of the short posterior ciliary arteries were seen at or around MNVs in 8 of the 17 eyes. In these eyes, the short posterior ciliary artery was filled first or almost simultaneously with the filling of the MNV, followed by a laminar filling of the DCVs. In one eye, afferent arterioles from the short posterior ciliary arteries and efferent venules connected to DCVs were seen. Conclusion Dilated choroidal veins are present below or around MNVs in about 30% of eyes with myopic MNVs. Our findings suggest that an MNV might be a vascular unit consisting of short posterior ciliary arteries, afferent arterioles, efferent venules, and DCVs.

Purpose Several studies have demonstrated increased auditory thresholds in patients with Parkinson's disease (PD) based on subjective tonal audiometry. However, the pathophysiological mechanisms underlying auditory dysfunction in PD remain elusive. The primary aim of this study was to investigate cochlear and olivocochlear function in PD using objective measurements and to assess the effect of dopaminergic medication on auditory function. Method Eighteen patients with PD and 18 gender- and age-matched healthy controls (HCs) were included. Patients with PD participated in medication on and off conditions. Linear mixed models were used to determine the effect of PD on tonal audiometry, transient evoked and distortion product otoacoustic emissions (OAEs), and efferent suppression (ES). Results Tonal audiometry revealed normal auditory thresholds in patients with PD for their age across all frequencies. OAE signal amplitudes demonstrated a significant interaction effect between group (PD vs. HC) and frequency, indicating decreased OAEs at low frequencies and increased OAEs at high frequencies in patients with PD. No significant differences were found between patients with PD and HCs regarding ES. In addition, no significant effect of medication status was found on auditory measurements in patients with PD. Conclusions Altered OAEs support the hypothesis of cochlear alterations in PD. No evidence was found for the involvement of the medial olivocochlear system. Altogether, OAEs may provide an objective early indicator of auditory alterations in PD and should complement subjective tonal audiometry when assessing and monitoring auditory function in PD.

Vestibular effects linked to eye movements have been extensively investigated, however, the effect of eye movements on the vestibular is relatively unknown. In this study, vestibular responses to horizontal pursuit and saccadic eye movements were examined in healthy individuals. Visual stimuli were presented to nineteen participants (27.7 ± 5.74 (SD) years, 11 female) using a virtual reality headset whilst the vestibular responses were simultaneously recorded using Electrovestibulography (EVestG). The average field potentials (FP) of three segments 1) prior to (Pre-Background), 2) during (Movement), and 3) after ceasing the visual stimulus (Post-Background) were extracted and the action potential (AP) area used as one feature. Both pursuit and saccadic eye movements resulted in a smaller average AP area during the Movement compared to Pre-Background (P = 0.002). Pursuit and saccadic eye movements also resulted in significantly longer time intervals between the low frequency (approximately 10 Hz) modulations of FPs detected during Movement compared to the Pre-Background (P ≤ 0.001). Moreover, a comparison between rightward and leftward saccades indicated no significant difference between the two directions for the FP and time interval features (P > 0.37). These findings suggest that pursuit and saccade eye movements inhibit the activity of both the central (postulated efferent pathways) and peripheral (afferent) vestibular system. We hypothesize that the purpose of this vestibular inhibition is to limit the vestibulo-ocular reflex and optokinetic response. Additionally, the insensitivity of the vestibular system to the saccade directions with a stationary head provides anecdotal evidence on the bilateral efferent projections to the vestibular afferent and hair cells.

BACKGROUND Renal denervation (RDN) is effective at lowering blood pressure. However, it is unknown if ablative procedures elicit sympathetic denervation of the kidneys in humans. The aim of this investigation was to assess sympathetic innervation of the renal cortex following perivascular chemical RDN, which may be particularly effective at ablating perivascular efferent and afferent nerves. METHODS Seven hypertensive patients (4F:3M; 50–65 years) completed PET–CT sympathetic neuroimaging of the renal cortex using 11C-methylreboxetine (11C-MRB, norepinephrine transporter ligand) and 6-[18F]-fluorodopamine (18F-FDA; substrate for the cell membrane norepinephrine transporter) before and 8 weeks after chemical RDN (Peregrine System Infusion Catheter, Ablative Solutions; n = 4; 2F:2M) or control renal angiography (n = 3; 2F:1M). Patients completed physiological phenotyping including 24-hour ambulatory blood pressure, hemodynamics, muscle sympathetic nerve activity, and 24-hour urine collection. RESULTS RDN decreased 11C-MRB-derived radioactivity by ~30% (Δ 11C-MRB/chamber: −0.95 a.u. confidence interval (CI): −1.36 to −0.54, P = 0.0002), indicative of efferent RDN. In contrast, 18F-FDA-derived radioactivity increased (Δ 18F-FDA/chamber: 2.72 a.u. CI: 0.73–4.71, P = 0.009), consistent with reduced vesicular turnover. Controls showed no change in either marker. Ambulatory systolic pressure decreased in 3 of 4 patients (−9 mm Hg CI: −27 to 9, P = 0.058), and central systolic pressure decreased in all patients (−23 mm Hg CI: −51 to 5, P = 0.095). CONCLUSIONS These results are the first to show efferent sympathetic denervation of the renal cortex following RDN in humans. Further studies of mechanisms underlying variable blood pressure lowering in the setting of documented RDN may provide insights into inconsistencies in clinical trial outcomes. CLINICAL TRIALS REGISTRATION Trial Number NCT03465917.

We used a finger force matching task to explore the role of efferent signals in force perception. Healthy, young participants performed accurate force production tasks at different force levels with the index and middle fingers of one hand (task-hand). They received visual feedback during an early part of each trial only. After the feedback was turned off, the force drifted toward lower magnitudes. After 5 s of the drift, the participants matched the force with the same finger pair of the other hand (match-hand). The match-hand consistently overshot the task-hand force by a magnitude invariant over the initial force levels. During force matching, both hands were lifted and lowered smoothly to estimate their referent coordinate (RC) and apparent stiffness values. These trials were performed without muscle vibration and under vibration applied to the finger/hand flexors or extensors of the task-hand or match-hand. Effects of vibration were seen in the match-hand only; they were the same during vibration of flexors and extensors. We interpret the vibration-induced effects as consequences of using distorted copies of the central commands to the task-hand during force matching. In particular, using distorted copies of the RC for the antagonist muscle group could account for the differences between the task-hand and match-hand. We conclude that efferent signals may be distorted before their participation in the perceptual process. Such distortions emerge spontaneously and may be amplified by the response of sensory endings to muscle vibration combined over both agonist and antagonist muscle groups.

OBJECTIVES Otoacoustic emissions, a byproduct of active cochlear mechanisms, exhibit a higher magnitude in females than in males. The relatively higher levels of androgen exposure in the male fetus are thought to cause this difference. Postnatally, the onset of puberty is also associated with the androgen surge in males. In this study, we investigated sexual dimorphism in age-related changes in stimulus-frequency otoacoustic emissions for children. DESIGN In a retrospective design, stimulus-frequency otoacoustic emissions were analyzed from a cross-sectional sample of 170 normal-hearing children (4 to 12 years) and 67 young adults. Wideband acoustic immittance and efferent inhibition measures were analyzed to determine the extent to which middle ear transmission and efferent inhibition can account for potential sex differences in stimulus-frequency otoacoustic emissions. RESULTS Male children showed a significant reduction in otoacoustic emission magnitudes with age, whereas female children did not show any such changes. Females showed higher stimulus-frequency otoacoustic emission magnitudes compared with males. However, the effect size of sex differences in young adults was larger compared with children. Unlike the otoacoustic emission magnitude, the noise floor did not show sexual dimorphism; however, it decreased with age. Neither the wideband absorbance nor efferent inhibition could account for the sex differences in stimulus-frequency otoacoustic emissions. CONCLUSIONS The cochlear-amplifier function remains robust in female children but diminishes in male children between 4 and 12 years of age. We carefully eliminated lifestyle, middle ear, and efferent factors to conclude that the androgen surge associated with puberty likely caused the observed masculinization of stimulus-frequency otoacoustic emissions in male children. These findings have significant theoretical consequences. The cochlea is considered mature at birth; however, the present findings highlight that functional cochlear maturation, as revealed by otoacoustic emissions, can be postnatally influenced by endogenous hormonal factors, at least in male children. Overall, work reported here demonstrates sexual dimorphism in the functional cochlear maturational processes during childhood.

OBJECTIVE: The medial olivocochlear (MOC) reflex provides efferent feedback from the brainstem to cochlear outer hair cells. Physiologic studies have demonstrated that the MOC reflex is involved in “unmasking” of signals-in-noise at the level of the auditory nerve; however, its functional importance in human hearing remains unclear. DESIGN: This study examined relationships between pre-neural measurements of MOC reflex strength (click-evoked otoacoustic emission inhibition; CEOAE) and neural measurements of speech-in-noise encoding (speech frequency following response; sFFR) in four conditions (Quiet, Contralateral Noise, Ipsilateral Noise, and Ipsilateral + Contralateral Noise). Three measures of CEOAE inhibition (amplitude reduction, effective attenuation, and input-output slope inhibition) were used to quantify pre-neural MOC reflex strength. Correlations between pre-neural MOC reflex strength and sFFR “unmasking” (i.e., response recovery from masking effects with activation of the MOC reflex in time and frequency domains) were assessed. STUDY SAMPLE: 18 young adults with normal hearing. RESULTS: sFFR unmasking effects were insignificant, and there were no correlations between pre-neural MOC reflex strength and sFFR unmasking in the time or frequency domain. CONCLUSION: Our results do not support the hypothesis that the MOC reflex is involved in speech-in-noise neural encoding, at least for features that are represented in the sFFR at the SNR tested.

Introduction . The lymphatic system maintains a steady state of organism and plays crucial role in a volume regulation of fluid surrounding the organs. The researching goal is to study the fluid redistribution process and to reveal adrenoceptive renal innervation of its lymphatic nodes in toxic hepatitis. Materials and methods . We studied the rat kidneys and their renal lymphatic nodes. The lymph flow of renal nodes and its adrenergic innervation were evaluated. Results . Rats with toxic hepatitis showed the decreasig fluorescence of adrenergic nerves and absence of the single neurons in kidney tissue and pelvis. Nerves in the renal parenchyma adjacent to the lymphatic nodes had a weak fluorescence. The average decreasing of lymph flow, volume of blood plasm and diuresis was 35, 21 and 60 %, correspondently. The disturbance of fluid redistribution, whole protein and electrolytes were observed. Conclusions . Toxic hepatitis leads to the destruction of adrenergic innervation in the tissues and blood vessels of the kidneys and renal lymph nodes, the disappearance of small terminals of nerves and part of varicose thickenings, the depots of catecholamines. This causes the diffusion of catecholamines into the surrounding tissues, suppressing the efferent signaling of nervous processes. The rats with hepatitis have had an impaired water-salt homeostasis resulted in a decreasing volume of plasma, circulating blood and lymph flow. The lymphatic system in hepatitis promotes the uptake of potassium and calcium ions released from the bloodstream, preventing them from being excreted in the urine.

To report stoma stenosis rates and efferent channel (EC) complications at long term follow-up for Turin pouch (TP). This is a retrospective analysis of the prospectively maintained database of patients who underwent TP between March 2006 and May 2018. The TP is a U-shaped right colon pouch. The EC was conceived by the tubularization of 5 cm of the colon wall with the use of a stapler and sutured to the skin (EC-cutaneostomy). The ureters are sutured separately to the last 10 cm of ileum before the ileocecal valve. In literature, catheterization problems have been described on average in 20.3% of patients and stoma stenosis in 19.5% of the patients with flap valve systems. Thirty-eight consecutive patients underwent a TP procedure. The median age was 55 years (IQR: 52–60). Median operative time was 201 min (IQR: 170–210), median reconstructive time was 61 min (IQR: 55–65) and the blood loss was 244 ml (IQR: 150–300) and 4 patients (10.5%) needed blood transfusions. The median follow-up was 52 months (IQR: 37–92). Complete 24h continence was achieved in 34 (89%) patients. Seven (18.4%) patients reported difficulties in EC catheterization and 4 (10.5%) patients had stoma stenosis. This study is limited by the relatively small number of patients. In relation to similar systems, the TP seems to offer comparatively good functional results but EC and stoma complications were lower than other pouch variants in literature.

The system of measures for conservative rehabilitation of patients with cicatricial lesions during pre- and postoperative periods of deformity reconstruction includes local, medication, physiotherapeutic, balneological means and methods of efferent therapy. A positive effect of measures is achieved by reducing the level of auto-aggressive factors, which is displayed in a favorable clinical course of the process. The application of the system of measures allows timely providing favorable conditions for compensating general condition of convalescents and restoring or improving the impaired functions of the affected segments according to objective estimates by 1.75 times and according to patients estimates by 1.44 times.

The descending corticofugal fibers originate from the auditory cortex and exert control on the periphery via the olivocochlear efferents. Medial efferents are thought to enhance the discriminability of transient sounds in background noise. In addition, the observation of deleterious long-term effects of efferent sectioning on the response properties of auditory nerve fibers in neonatal cats supports an efferent-mediated control of normal development. However, the role of the efferent system in human hearing remains unclear. The objective of the present study was to test the hypothesis that the medial efferents are involved in the development of frequency discrimination in noise. The hypothesis was examined with a combined behavioral and physiological approach. Frequency discrimination in noise and efferent inhibition were measured in 5- to 12-yr-old children (n = 127) and young adults (n = 37). Medial efferent strength was noninvasively assayed with a rigorous otoacoustic emission protocol. Results revealed an age-mediated relationship between efferent inhibition and frequency discrimination in noise. Efferent inhibition strongly predicted frequency discrimination in noise for younger children (5–9 yr). However, for older children (>9 yr) and adults, efferent inhibition was not related to frequency discrimination in noise. These findings support the role of efferents in the development of hearing-in-noise in humans; specifically, younger children compared with older children and adults are relatively more dependent on efferent inhibition for extracting relevant cues in noise. Additionally, the present findings caution against postulating an oversimplified relationship between efferent inhibition and measures of auditory perception in humans. NEW & NOTEWORTHY Despite several decades of research, the functional role of medial olivocochlear efferents in humans remains controversial and is thought to be insignificant. Here it is shown that medial efferent inhibition strongly predicts frequency discrimination in noise for younger children but not for older children and adults. Young children are relatively more dependent on the efferent system for listening-in-noise. This study highlights the role of the efferent system in hearing-in-noise during childhood development.

Sacral nerve stimulation (SNS) was reported to improve 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis in rats. The aim of this study was to investigate whether the SNS anti-inflammatory effect is mediated via the local sacral splanchnic nerve or the spinal afferent-vagal efferent-colon pathway. Under general anesthesia, rats were administrated with TNBS intrarectally, and bipolar SNS electrodes were implanted unilaterally at S3. The sacral and vagal nerves were severed at different locations for the assessment of the neural pathway. SNS for 10 days improved colonic inflammation only in groups with intact afferent sacral nerve and vagus efferent nerve. SNS markedly increased acetylcholine and anti-inflammatory cytokines (IL-10) and decreased myeloperoxidase and proinflammatory cytokines (IL-2, IL-17A, and TNF-α) in colon tissues. SNS increased the number of c-fos-positive cells in the brain stem and normalized vagal activity measured by spectral analysis of heart rate variability. SNS exerts an anti-inflammatory effect on TNBS-induced colitis by enhancing vagal activity mediated mainly via the spinal afferent-brain stem-vagal efferent-colon pathway. NEW & NOTEWORTHY Our findings support that there is a possible sacral afferent-vagal efferent pathway that can transmit sacral nerve stimulation to the colon tissue. Sacral nerve stimulation can be carried out by spinal cord afferent to the brain stem and then by the vagal nerve (efferent) to the target organ.

Introducción. En mamíferos, el control de la temperatura corporal es vital. El estado de consciencia y control motor en humanos, ocurren a una temperatura de 37°C y las desviaciones pueden alterar las propiedades celulares, generando disfunciones fisiológicas. En especies como los roedores (su relación área de superficie/volumen facilita la pérdida de calor) mantienen temperaturas basales cercanas a los 30°C. Distinto es con animales como los paquidermos, cuya temperatura es menor comparada con los humanos. El objetivo es identificar los aspectos fisiológicos de la termorregulación. Descripción de temas tratados. Revisión descriptiva de la literatura de artículos publicados en diferentes bases de datos. La termorregulación es la capacidad del cuerpo para establecer y mantener su temperatura, regulando producción y pérdida de calor para optimizar la eficiencia de procesos metabólicos. El protagonismo lo tiene el sistema nervioso central y su control neurohormonal en múltiples niveles. El centro regulador térmico está en el hipotálamo anterior. Este recibe información de los receptores de grandes vasos, vísceras abdominales, médula espinal y de la sangre que perfunde el hipotálamo. Cuando aumenta la temperatura central, el termorregulador activa fibras eferentes del sistema nervioso autónomo, provocando pérdida de calor por convección y evaporación. Ante el descenso de temperatura, la respuesta es disminuir la pérdida de calor (vasoconstricción y menor sudoración); además, incrementar la producción de calor, intensificando la actividad muscular. Conclusión. La termorregulación es liderada por el hipotálamo, quien regula aumento y disminución de la temperatura respondiendo a las necesidades del organismo para llegar a la homeostasis y compensación, enfrentando las alteraciones de la temperatura ambiental. Introduction. In mammals, controlling body temperature is vital. Consciousness and motor control in humans occur at a temperature of 37°C and any deviation can alter the cellular properties, generating physiological dysfunctions. In species such as rodents (their surface area/volume ratio facilitates heat loss) they maintain basal temperatures close to 30°C. This is different with animals such as pachyderms, whose temperature is lower compared to humans. This article aims to Identify the physiological aspects of thermoregulation. Topics. Descriptive literature review of articles published in different databases. Thermoregulation is the body’s ability to establish and maintain its temperature, regulating heat production and loss to optimize the efficiency of metabolic processes. The main actor in this process is the central nervous system and its neuro-hormonal control on multiple levels. The thermal regulating center is located in the anterior hypothalamus. It receives information from the receptors of large vessels, abdominal viscera, spinal cord and the blood that perfuses the hypothalamus. When the core temperature increases, the thermoregulator activates efferent fibers of the autonomic nervous system, causing heat loss by convection and evaporation. When the temperature drops, the response is to decrease heat loss (vasoconstriction and less sweating); in addition, increase heat production by intensifying muscle activity. Conclusion. Thermoregulation is led by the hypothalamus, which regulates temperature increase and decrease by responding to the organism’s need to reach homeostasis and compensation, facing the alterations of the ambient temperature. Introdução. Nos mamíferos, o controle da temperatura corporal é vital. O estado de consciencia e controle motor em humanos ocorre a uma temperatura de 37 °C e os desvios podem alterar as propriedades celulares, gerando disfunções fisiológicas. Espécies como os roedores (a sua relação superfície/volume, facilita a perda de calor), mantêm a temperatura basal próxima de 30 °C. É diferente em animais como paquidermes, cuja temperatura é mais baixa em comparação aos humanos. Objetivo. Identificar os aspectos fisiológicos da termorregulação. Desenvolvimento. Revisão descritiva da literatura de artigos publicados em diferentes bases de dados. A termorregulação é a capacidade do corpo de estabelecer e manter sua temperatura, regulando a produção e a perda de calor para otimizar a eficiência dos processos metabólicos. O sistema nervoso central tem o papel principal, assim como seu controle neuro-hormonal em múltiplos níveis. O centro de regulação térmica está no hipotálamo anterior, que recebe informações dos receptores de grandes vasos, vísceras abdominais, medula espinhal e do sangue distribuído pelo hipotálamo. Quando a temperatura central aumenta, o termorregulador ativa fibras eferentes do sistema nervoso autônomo, causando perda de calor por convecção e evaporação. Dada a diminuição da temperatura, a resposta é reduzir a perda de calor (vasoconstrição e menos transpiração), além de aumentar a produção de calor, intensificando a atividade muscular. Conclusão. A termorregulação é liderada pelo hipotálamo, que regula o aumento e a diminuição da temperatura, respondendo às necessidades do organismo de atingir a homeostase e a compensação, enfrentando mudanças na temperatura ambiente. Cómo citar: Picón-Jaimes YA, Orozco-Chinome JE, Molina-Franky J, Franky-Rojas MP. Control central de la temperatura corporal y sus alteraciones: fiebre, hipertermia e hipotermia. MedUNAB. 2020;23(1):118-130. doi:10.29375/01237047.3714

The present study aims to investigate structural and functional connectivity (SC and FC) in cerebello-cerebral circuit in idiopathic generalized epilepsy (IGE). Diffusion tensor imaging and resting-state imaging data were collected from 57 patients with IGE and 66 controls in the present study. First, we performed bidirectional probabilistic fiber tracking between cerebellum and cerebral cortex, consisting of cerebellar efferent and afferent fibers. Then, strength of structural connectivity (SCS), fractional anisotropy (FA), mean diffusivity (MD), and radial diffusivity (RD) were extracted and compared between groups. Finally, cerebellar FC with cerebral cortex was evaluated with seeding at dentate nucleus. Between-group comparisons were performed using t tests with a significant level setting at p

All leukocytes can get entrance into the draining lymph nodes via the afferent lymphatics but only lymphoid cells can leave the nodes. The molecular mechanisms behind this phenomenon have remained unknown. We employed genome wide microarray analyses of the subcapsular sinus and lymphatic sinus (LS) endothelial cells and found Robo4 to be selectively expressed on LS lymphatics. Further analyses showed high Robo4 expression in lymphatic vessels of Peyer’s patches, which only have efferent lymphatic vessels. In functional assays, Robo4-deficient animals showed accumulation of naive B cells (CD19+/CD62Lhi/CD44lo) in Peyer’s patches, whereas no difference was seen within other lymphocyte subtypes. Short-term lymphocyte homing via high endothelial venules to peripheral and mesenteric lymph nodes and Peyer’s patches was also slightly impaired in Robo4 knockout animals. These results show for the first time, selective expression of Robo4 in the efferent arm of the lymphatics and its role in controlling the turnover of a subset of B lymphocytes from Peyer’s patches.

The infralimbic cortex of the cerebral hemispheres is characterized by an extensive system of afferent and efferent connections with cortical, subcortical, bainstem structures and the spinal cord, which ensure its participation in the higher mechanisms of regulation of the functions of the visceral sphere. At the same time, the involvement of the infralimbic cortex in the mechanisms of cortical modulation of visceral nociception, both acute and chronic, seems to be poorly understood. In this work, using an experimental model of abdominal pain on two groups of urethane anesthetized rats (normal rats and rats with experimental colitis), we studied the effects of electrical stimulation of the infralimbic cortex on the neuronal (responses of neurons of the caudal ventrolateral reticular formation) and systemic (changes in arterial blood pressure) reactions induced by nociceptive distension of the colorectal region of colon. It has been found that in rats of both groups nociceptive colorectal distension was accompanied by both excitatory and inhibitory reactions of neurons of the ventrolateral reticular formation, as well as depressor changes in blood pressure. Electrical stimulation of the infralimbic cortex increased excitatory and decreased inhibitory neuronal responses to visceral painful stimulation and also enhanced nociceptive depressor responses in both normal rats and rats with colitis. This effect was more pronounced in the group of healthy animals. In general, the influence of the infralimbic cortex on nociceptive neurons of the ventrolateral reticular formation and vascular responses to visceral pain can be considered as facilitating visceral nociception. Quantitative differences in the effects of cortical stimulation in normal rats and rats with colitis are possibly related to differences in the brain processing of acute visceral pain and pain complicated by chronic inflammation. One of the possible mechanisms of cortical influence on visceral nociception may be modulation of the current activity of nociceptive neurons of the caudal ventrolateral reticular formation, directly or indirectly involved in the descending control of visceral pain.

RESUMO Objetivo investigar o efeito inibitório da via auditiva eferente na síndrome de Turner e relacionar com o perfil citogenético. Método estudo descritivo transversal com grupo de comparação. Amostra: Grupo estudo formado por 40 pacientes com síndrome de Turner (17,6 anos); e Grupo controle constituído por 54 indivíduos (18,9 anos), do sexo feminino sem síndrome. Os indivíduos selecionados foram submetidos à pesquisa do efeito inibitório da via auditiva eferente. Resultados A média do Efeito inibitório da via auditiva eferente no grupo estudo na orelha direita foi 0,4 dB e no grupo comparação foi de 1,9 dB, entretanto na orelha esquerda a média do efeito inibitório da via auditiva eferente foi 1,4 dB no grupo estudo e 0,8 dB no grupo comparação. O efeito inibitório da via auditiva eferente foi presente em 14 indivíduos com monossomia e em 15 com outras alterações citogenéticas. Conclusão No grupo estudo o valor do efeito inibitório da via auditiva eferente foi significantemente maior na orelha esquerda e significativamente menor que o grupo controle na direita. Não houve diferença significativa no efeito inibitório da via auditiva eferente entre os tipos de cariótipo. ABSTRACT Purpose The goal of this study is to investigate the efferent auditory pathways inhibition in Turner's syndrome and to relate it to the cytogenetic profile. Methods This is a cross-sectional study with a comparison group. A sample with 94 participants divided into two groups: The study group was a sample of 40 patients diagnosed with Turner’s syndrome (17.6 years of age). The control group was composed of 54 volunteers (18.9 years of age), female, without syndrome. The selected individuals were submitted to efferent auditory pathways inhibition research. Results The mean of the inhibitory effect of the efferent auditory pathway in the study group in the right ear was 0.4 dB and in the comparison group it was 1.9 dB, however in the left ear the mean of the inhibitory effect of the efferent auditory pathway was 1.4 dB in the study group and 0.8 dB in the comparison group. The inhibitory effect of the efferent auditory pathway was present in 14 individuals with monosomy and in 15 with other cytogenetic alterations. Conclusions In the study group, the efferent auditory pathways inhibition value was significantly higher in the left ear and significantly lower than the control group in the right ear. There was no significant difference in efferent auditory pathways inhibition of right ear and left ear between the karyotype types.

Contains fulltext : 249492.pdf (Publisher’s version ) (Open Access) The centrally-projecting Edinger-Westphal nucleus (EWcp) hosts a large population of neurons expressing urocortin 1 (Ucn1) and about half of these neurons also express the leptin receptor (LepRb). Previously, we have shown that the peripheral adiposity hormone leptin signaling energy surfeit modulates EWcp neurons' activity. Here, we hypothesized that Ucn1/LepRb neurons in the EWcp would act as a crucial neuronal node in the brain-white adipose tissue (WAT) axis modulating efferent sympathetic outflow to the WAT. We showed that leptin bound to neurons of the EWcp stimulated STAT3 phosphorylation, and increased Ucn1-production in a time-dependent manner. Besides, retrograde transneuronal tract-tracing using pseudorabies virus (PRV) identified EWcp Ucn1 neurons connected to WAT. Interestingly, reducing EWcp Ucn1 contents by ablating EWcp LepRb-positive neurons with leptin-saporin, did not affect food intake and body weight gain, but substantially (+26%) increased WAT weight accompanied by a higher plasma leptin level and changed plasma lipid profile. We also found that ablation of EWcp Ucn1/LepRb neurons resulted in lower respiratory quotient and oxygen consumption one week after surgery, but was comparable to sham values after 3 and 5 weeks of surgery. Taken together, we report that EWcp/LepRb/Ucn1 neurons not only respond to leptin signaling but also control WAT size and fat metabolism without altering food intake. These data suggest the existence of a EWcp-WAT circuitry allowing an organism to recruit fuels without being able to eat in situations such as the fight-or-flight response.

Calcitonin-gene-related peptide (CGRP) is a lateral olivocochlear (LOC) efferent neurotransmitter. Depression of sound-driven auditory brainstem response amplitude in CGRP-null mice suggests the potential for endogenous CGRP release to upregulate spontaneous and/or sound-driven auditory nerve (AN) activity. We chronically infused CGRP into the guinea pig cochlea and evaluated changes in AN activity as well as outer hair cell (OHC) function. The amplitude of both round window noise (a measure of ensemble spontaneous activity) and the synchronous whole-nerve response to sound (compound action potential, CAP) were enhanced. Lack of change in both onset adaptation and steady state amplitude of sound-evoked distortion product otoacoustic emission (DPOAE) responses indicated CGRP had no effect on OHCs, suggesting the origin of the observed changes was neural. Combined with results from the CGRP-null mice, these results appear to confirm that endogenous CGRP enhances auditory nerve activity when released by the LOC neurons. However, infusion of the CGRP receptor antagonist CGRP (8–37) did not reliably influence spontaneous or sound-driven AN activity, or OHC function, results that contrast with the decreased ABR amplitude measured in CGRP-null mice.

Introduction: The cholinergic anti-inflammatory pathway (CAIP) has been proposed as an efferent neural pathway dampening the systemic inflammatory response via the spleen. The CAIP activates the splenic neural plexus and a subsequent series of intrasplenic events, which at least require a close association between sympathetic nerves and T cells. Knowledge on this pathway has mostly been derived from rodent studies and only scarce information is available on the innervation of the human spleen. This study aimed to investigate the sympathetic innervation of different structures of the human spleen, the topographical association of nerves with T cells and age-related variations in nerve distribution.Materials and Methods: Spleen samples were retrieved from a diagnostic archive and were allocated to three age groups; neonates, 10–25 and 25–70 years of age. Sympathetic nerves and T cells were identified by immunohistochemistry for tyrosine hydroxylase (TH) and the membrane marker CD3, respectively. The overall presence of sympathetic nerves and T cells was semi-automatically quantified and expressed as total area percentage. A predefined scoring system was used to analyze the distribution of nerves within different splenic structures.Results: Sympathetic nerves were observed in all spleens and their number appeared to slightly increase from birth to adulthood and to decrease afterward. Irrespective to age, more than halve of the periarteriolar lymphatic sheaths (PALSs) contained sympathetic nerves in close association with T cells. Furthermore, discrete sympathetic nerves were observed in the capsule, trabeculae and red pulp and comparable to the total amount of sympathetic nerves, showed a tendency to decrease with age. No correlation was found between the number of T cells and sympathetic nerves.Conclusion: The presence of discrete sympathetic nerves in the splenic parenchyma, capsule and trabecular of human spleens could suggest a role in functions other than vasoregulation. In the PALS, sympathetic nerves were observed to be in proximity to T cells and is suggestive for the existence of the CAIP in humans. Since sympathetic nerve distribution shows interspecies and age-related variation, and our general understanding of the relative and spatial contribution of splenic innervation in immune regulation is incomplete, it remains difficult to estimate the anti-inflammatory potential of targeting splenic nerves in patients.

The auditory efferent system, especially the medial olivocochlear reflex (MOCR), is implicated in both typical auditory processing and in auditory disorders in animal models. Despite the significant strides in both basic and translational research on the MOCR, its clinical applicability remains under-utilized in humans due to the lack of a recommended clinical method. Conventional tests employ broadband noise in one ear while monitoring change in otoacoustic emissions (OAEs) in the other ear to index efferent activity. These methods, (1) can only assay the contralateral MOCR pathway and (2) are unable to extract the kinetics of the reflexes. We have developed a method that re-purposes the same OAE-evoking click-train to also concurrently elicit bilateral MOCR activity. Data from click-train presentations at 80 dB peSPL at 62.5 Hz in 13 young normal-hearing adults demonstrate the feasibility of our method. Mean MOCR magnitude (1.7 dB) and activation time-constant (0.2 s) are consistent with prior MOCR reports. The data also suggest several advantages of this method including, (1) the ability to monitor MEMR, (2) obtain both magnitude and kinetics (time constants) of the MOCR, (3) visual and statistical confirmation of MOCR activation.

The sense of body ownership is being increasingly studied by manipulating incoming signals from the periphery with local anesthetics. We sought to understand how altered proprioception induced by anesthesia triggered a traumatic jersey finger, immediately postoperatively, in two patients who underwent surgical carpal tunnel release. Multiple mechanisms contributed to these postoperative injuries associated with a fall. Hand anesthesia deprives the brain of important afferent sensory information and modifies hand size perception in the brain. Moreover, it blocks efferent motor signals that contribute to the perception of hand position with sensory afferent signals. When the patients fell, their movement control was inadequate, generating a strong contraction of the hand extrinsic flexor muscles, against forceful distal phalanx extension. Lastly, both patients had removed their numb operated hand from their arm sling. Disrupted sensory and motor paths modify self-attribution of the hand, and thus halt adequate efferent commands. Protecting the operated hand until full sensory and motor control is regained could have prevented such rare accidents from happening. Level of evidence: V.

The key physiological parameters that determine glomerular filtration rate levels are renal plasma flow, filtration fraction, intraglomerular pressure, and balance between afferent and efferent glomerular arteriolar resistance. The evaluation of the balance between afferent and efferent glomerular arteriolar resistance might be useful for the classification of diabetic kidney disease.

BACKGROUND The current study attempted to assess efferent auditory system functioning in individuals with auditory neuropathy spectrum disorder (ANSD) using a new approach, contralateral suppression of SOAE, which has not yet been extensively researched. METHODS Spontaneous otoacoustic emissions (SOAEs) were recorded in a total of 62 ears, divided into 2 groups. Group I comprised of 31 ears with normal hearing (NH), while group II consisted of 31 ears with ANSD. All the participants considered for the study were in the age range of 18-45 years. Synchronized SOAE were recorded using the ILO V6 OAE instrument with and without noise (broadband noise, 50 dB SPL) in the contralateral ear. The frequency and amplitude shifts secondary to the introduction of contralateral noise were analyzed. RESULTS The results of the study showed a statistically significant high-frequency shift of SOAE with contralateral noise for the NH and ANSD groups. In addition, the NH group also exhibited a statistically significant reduction in SOAE amplitude in contralateral noise conditions. Such a reduction in SOAE amplitude was not observed in individuals with ANSD. CONCLUSION The absence of suppression of SOAE amplitude suggests efferent damage in individuals with ANSD. The shift in SOAE frequency toward higher frequency in the ANSD group, which is similar to NH group, is suggestive of differential allotment of medial olivocochlear (MOC) mechanism in individuals with ANSD, which codes for contralateral frequency changes and not for amplitude changes.

Repetitive transcranial magnetic stimulation (rTMS) may support motor function recovery in patients with incomplete spinal cord injury (iSCI). Its effectiveness mainly depends on the applied algorithm. This clinical and neurophysiological study aimed to assess the effectiveness of high-frequency rTMS in iSCI patients at the C2–Th12 levels. rTMS sessions (lasting 3–5 per month, from 2 to 11 months, 5 months on average) were applied to 26 iSCI subjects. The motor cortex was bilaterally stimulated with a frequency at 20–25 Hz and a stimulus strength that was 70–80% of the resting motor threshold (15.4–45.5% maximal output) during one therapeutic session. Surface electromyography (sEMG) recordings at rest and during maximal contractions and motor evoked potential (MEP) recordings were performed from the abductor pollicis brevis (APB) and the tibialis anterior (TA) muscles. The same neurophysiological studies were also performed in patients treated with kinesiotherapy only (K group, n = 25) and compared with patients treated with both kinesiotherapy and rTMS (K + rTMS). A decrease in sEMG amplitudes recorded at rest from the APB muscles (p = 0.001) and an increase in sEMG amplitudes during the maximal contraction of the APB (p = 0.001) and TA (p = 0.009) muscles were found in the K + rTMS group. A comparison of data from MEP studies recorded from both APB and TA muscles showed significant changes in the mean amplitudes but not in latencies, suggesting a slight improvement in the transmission of spinal efferent pathways from the motor cortex to the lower spinal centers. The application of rTMS at 20–25 Hz reduced spasticity in the upper extremity muscles, improved the recruitment of motor units in the upper and lower extremity muscles, and slightly improved the transmission of efferent neural impulses within the spinal pathways in patients with C2–Th12 iSCI. Neurophysiological recordings produced significantly better parameters in the K + rTMS group of patients after therapy. These results may support the hypothesis about the importance of rTMS therapy and possible involvement of the residual efferent pathways including propriospinal neurons in the recovery of the motor control of iSCI patients.

Sound lateralization/localization is one of the most important auditory processing abilities, which plays approved role in auditory streaming and speech perception in challenging situations like noisy places. In addition to the main role of lower brainstem centers like superior olivary complex in sound lateralization, efferent auditory system effects on improving auditory skills in everyday auditory challenging positions were revealed. This study evaluated noise effects on lateralization scores in correlation with an objective electrophysiologic test (Speech-ABR in noise), which objectively shows cumulative effects of the afferent and efferent auditory systems at the inferior colliculus and upper brainstem pathway. Fourteen normal-hearing subjects in the age range of 18 to 25 participated in this study. Lateralization scores in the quiet and noisy modes were evaluated. Speech-ABR in both ears for quiet mode and three different contralateral noise levels (SNR = + 5, 0, − 5) were recorded, too. Correlation of lateralization scores and Speech-ABR changes in noise was studied. Significant decrease of lateralization scores with latency increase and amplitude decrease of Speech-ABR transient peaks (V, A, O) was seen with noise presentation. A high positive correlation between lateralization decrease with latency increase of onset peaks (V, A) and amplitude decrease of transient peaks (V, A, O) was found in low signal-to-noise ratios. The study revealed that in high challenging auditory situations like auditory lateralization in noise, upper brainstem centers and pathways play a facilitative role for main auditory lateralization centers in lower levels.

Background Vagus nerve stimulation (VNS) has become an increasingly popular procedure for the treatment of epilepsy and depression. Significant complications or side effects associated with VNS surgery may result from either the inadvertent direct injury to the vagus nerve as part of the surgical approach, placement of the electrode, or the concomitant stimulation of vagal efferent fibers. To mitigate these effects, the recognition of anatomic variants that may place the nerve at increased risk is necessary. Case Description During microsurgical dissection of the carotid sheath for the implantation of a vagus nerve stimulator in a 17-year-old male patient with refractory epilepsy, additional nonidentified nerve tissue was found running parallel to the vagus nerve. These fibers were two thirds of the thickness of the vagus nerve and ran medial to it, from the most superior to the most inferior aspect of the carotid sheath dissection, found at a distance of at least 4 cm in a craniocaudal direction. This duplicated nerve did not appear to branch from the vagal trunk nor exit the sheath but rather paralleled the course of the vagus nerve. The parallel course and the proximity of the unidentified nerve make this structure likely to be a duplicated vagus nerve. Conclusions This is the first reported case of cervical vagus nerve duplication presented in the literature. Surgeons performing VNS implantations should be cognizant of this potential anomaly in order to avoid inadvertent injury to the nerve.

El neurotrauma constituye en la actualidad un problema de salud pública, siendo más común en los adolescentes y adultos jóvenes, y su principal causa los accidentes de tránsito. En muchas ocasiones este tipo de lesiones comprometen vías visuales aferentes, eferentes y autonómicas, las cuales son conocidas como lesiones neuro-oftálmicas. Para su diagnóstico se requiere de un buen examen físico en el paciente y así determinar el tratamiento adecuado para la misma, con el objetivo de disminuir o erradicar la sintomatología con la que curse el paciente. Objetivo: Realizar una revisión de las lesiones neuro-oftálmicas más comunes en el paciente con neurotrauma, su diagnóstico y recomendaciones de manejo.

PURPOSE OF REVIEW This article discusses an approach to imaging in patients with neuro-ophthalmologic disorders, with emphasis on the clinical-anatomic localization of lesions affecting afferent and efferent visual function. RECENT FINDINGS Advances in MRI, CT, ultrasound, and optical coherence tomography have changed how neuro-ophthalmic disorders are diagnosed and followed in the modern clinical era. SUMMARY The advantages, disadvantages, and indications for various imaging techniques for neuro-ophthalmologic disorders are discussed, with a view to optimizing how these tools can be used to enhance patient care.

Compared to many other rodent species, naked mole rats (Heterocephalus glaber) have elevated auditory thresholds, poor frequency selectivity, and limited ability to localize sound. Because the cochlea is responsible for encoding and relaying auditory signals to the brain, we used immunofluorescence and quantitative image analysis to examine cochlear innervation in mature and developing naked mole rats compared to mice (Mus musculus), gerbils (Meriones unguiculatus), and Damaraland mole rats (Fukomys damarensis), another subterranean rodent. In comparison to mice and gerbils, we observed alterations in afferent and efferent innervation as well as their patterns of developmental refinement in naked and Damaraland mole rats. These alterations were, however, not always shared similarly between naked and Damaraland mole rats. Most conspicuously, in both naked and Damaraland mole rats, inner hair cell (IHC) afferent ribbon density was reduced, whereas outer hair cell afferent ribbon density was increased. Naked and Damaraland mole rats also showed reduced lateral and medial efferent terminal density. Developmentally, naked mole rats showed reduced and prolonged postnatal reorganization of afferent and efferent innervation. Damaraland mole rats showed no evidence of postnatal reorganization. Differences in cochlear innervation specifically between the two subterranean rodents and more broadly among rodents provides insight into the cochlear mechanisms that enhance frequency sensitivity and sound localization, maturation of the auditory system, and the evolutionary adaptations occurring in response to subterranean environments.

PurposeThe study aimed to assess the relationship between the level-dependent function of efferent inhibition and speech perception in noise across different intensities of suppressor and across different signal-to-noise ratios (SNRs) of speech.MethodTwenty-six young normal-hearing adults participated in the study. Contralateral suppression of transient evoked otoacoustic emissions (TEOAEs) was measured for 3 levels of suppressor (40, 50, and 60 dB SPL). Speech identification score (SIS) was measured at 5 ipsilateral SNR conditions (quiet, 0, −5, −10, and −15 dB), with and without contralateral broadband noise at 3 levels (40, 50, and 60 dB SPL). Furthermore, SNR-50 was measured with and without the same 3 levels of contralateral broadband noise.ResultsThe results showed that the suppression magnitude of TEOAE increased with an increase in suppressor level. However, neither SIS nor SNR-50 was influenced by the contralateral noise. In addition, SIS and SNR-50 did not show significant correlation with contralateral suppression of TEOAEs. This was true at all the SNRs and contralateral noise levels used in the study.ConclusionsThe findings suggest that the intensity of noise directly influences medial olivocochlear bundle–mediated efferent inhibition. However, the role of the medial olivocochlear bundle in regulating speech perception in noise needs to be revisited.Supplemental Materialhttps://doi.org/10.23641/asha.9336353

BACKGROUND Sinusoidal current stimuli preferentially activate C-nociceptors. Sodium channel isoforms NaV1.7 and NaV1.8 have been implicated in this. Sympathetic efferent neurons lack NaV1.8 and were explored upon sinusoidal activation. METHODS Quantitative Sudomotor Axon Reflex Test (QSART) was performed in hairy (n = 16) and glabrous (n = 12) skin. Responses of sympathetic efferents (n = 10) and nociceptive afferents (n = 21) to sinusoidal current stimulation (4 Hz, 0.05-0.15 mA) were recorded in humans by microneurography (n = 11). Activation of sympathetic units upon supra-threshold sinusoidal currents (>0.8 mA) was recorded in pigs (n = 8). RESULTS Sinusoidal stimuli (4 Hz, 0.4 mA) evoked weak sweat output (30 ml/h/m2 ) in hairy skin compared to rectangular pulses (4 Hz, 5 mA, 53 ml/h/m2 , p

Systemic anaphylaxis is a life-threatening and allergic reaction that affects various organs. We previously reported that, in the stomach, gastric vasoconstriction occurring at the late phase (15–55 min after injection of ovalbumin antigen) was observed in anesthetized rats sensitized with ovalbumin. In addition, anaphylaxis enhances gastric motility and delays emptying. However, the role of extrinsic autonomic nervous system on antigen-induced gastric alterations was not known. Thus, using the same rat anaphylaxis model, we aimed to determine the changes in the efferent and afferent autonomic nerve activities in the stomach during anaphylactic hypotension. The findings showed that injection of ovalbumin antigen caused substantial systemic hypotension in all sensitized rats. The efferent gastric sympathetic nerve activity (ef-GSNA), but not the efferent vagal nerve activity, increased only at the early phase (1–10 min after injection of ovalbumin antigen) and showed baroreceptor reflex, as evidenced by a stimulatory response to sodium nitroprusside-induced hypotension. In general, excitation of ef-GSNA could induce pylorus sphincter contraction and gastric vasoconstriction. In the present study, we found that sympathectomy attenuated the anaphylaxis-induced decrease in gastric flux but not the increase in gastric vascular resistance. Thus, the increase in ef-GSNA may cause anaphylactic pylorus sphincter contraction but not anaphylactic gastric vasoconstriction. On the other hand, the afferent gastric vagal nerve activity, but not the afferent sympathetic nerve activity, increased during the early phase of anaphylactic hypotension. However, vagotomy produced no effects on the anaphylactic gastric dysfunction. In conclusion, the gastric sympathetic nerves partly modulate stomach function during systemic anaphylaxis.

Multi-organ dysfunction is a major complication after spinal cord injury (SCI). In addition to local injury within the spinal cord, SCI causes major disruption to the peripheral organ innervation and regulation. The liver contains sympathetic, parasympathetic, and small sensory axons. The bi-directional signaling of sensory dorsal root ganglion (DRG) neurons that provide both efferent and afferent information is of key importance as it allows sensory neurons and peripheral organs to affect each other. SCI-induced liver inflammation precedes and may exacerbate intraspinal inflammation and pathology after SCI, which may be modulated by activity and exercise. In this study, we collected comprehensive gene expression data through RNA sequencing of liver tissue from rats with chronic SCI to determine the effects of activity and exercise on those expression patterns. The sequenced data are of high quality and show a high alignment rate to the Rn6 genome. Gene expression is demonstrated for genes associated with known liver pathologies. UCSC Genome Browser expression tracks are provided with the data to facilitate exploration of the samples., Design Type(s)gene expression analysis objective • stimulus or stress design • transcription profiling designMeasurement Type(s)gene expressionTechnology Type(s)RNA sequencingFactor Type(s)Spinal Cord Injury • Exercise • EnvironmentalVariable • biological replicateSample Characteristic(s)Rattus norvegicus • liver Machine-accessible metadata file describing the reported data (ISA-Tab format)

To evaluate the prevalence of extra-gastric direct connection between afferent and efferent veins of gastric varices (GVs) (i.e., EAEDC) and its clinical significance during balloon-occluded retrograde transvenous obliteration (BRTO). 57 patients who underwent BRTO for GVs obliteration were retrospectively enrolled in this study. Pre-procedural CT images were reviewed for the presence of EAEDC. Patients were categorized into group A (patients with EAEDC) and group B (Patients with no detectable EAEDC). Intraprocedural images were reviewed to see if EAEDCs could be seen and if additional techniques were used to preserve or occlude them. Post-procedural CT images were reviewed for GVs obliteration, portal/splenic vein thrombosis, EAEDC patency, and ascites exacerbation. Post-procedural esophageal varices aggravation was evaluated by upper endoscopy. 39 EAEDCs were identified in CT images of 35 patients (i.e., group A = 61.4%). Among them, only 20 EAEDCs were visualized during BRTO. In the remaining 22 patients, EAEDC was not identified in CT images or during BRTO (i.e., group B = 38.6%). There was no statistically significant difference between group A and B regarding post-BRTO GVs obliteration and portal/splenic vein thrombosis. Use of additional techniques to preserve EAEDC patency had significantly reduced the incidence of ascites and esophageal varices exacerbation (p = 0.036 and 0.028, respectively). In patients with EAEDC diameter ≥ 5 mm, EAEDC preservation or obliteration by coils or balloon had significantly reduced the injected sclerosant volume (p = 0.003). CT is very useful for EAEDC detection. EAEDC preservation may decrease the incidence of post-BRTO ascites and esophageal varices exacerbation.

Various lactobacilli have been suggested to exert beneficial effects in humans. In this study, we examined the effects of intraduodenal (ID) administration of heat-killed Lactobacillus delbrueckii LAB4 (LAB4) on activities of efferent sympathetic nerves innervating the liver and pancreas. Consequently, it was observed that ID administration of LAB4 significantly reduced either the efferent hepatic sympathetic nerve activity (hepatic-SNA) or pancreatic sympathetic nerve activity (pancreatic-SNA) in urethane-anaesthetised rats. Moreover, the effect of acute and chronic administration of LAB4 (1×109 cells/ml) on hyperglycaemia induced by intracranial injection of 2-deoxy-D-glucose (2DG) were examined in conscious rats. We found that LAB4 significantly inhibited 2DG-induced hyperglycaemia. These findings suggest that ID administration of heat-killed LAB4 might lower plasma glucose level via changes in the autonomic nervous system in rats.

The splanchnic anti-inflammatory pathway has been proposed as the efferent arm of the inflammatory reflex. Although much evidence points to the spleen as the principal target organ where sympathetic nerves inhibit immune function, a systematic study to locate the target organ(s) of the splanchnic anti-inflammatory pathway has not yet been made. In anesthetized rats made endotoxemic with lipopolysaccharide (LPS, 60 µg/kg iv), plasma levels of tumor necrosis factor-α (TNF-α) were measured in animals with cut (SplancX) or sham-cut (Sham) splanchnic nerves. We confirm here that disengagement of the splanchnic anti-inflammatory pathway in SplancX rats (17.01 ± 0.95 ng/ml, mean ± SE) strongly enhances LPS-induced plasma TNF-α levels compared with Sham rats (3.76 ± 0.95 ng/ml). In paired experiments, the responses of SplancX and Sham animals were compared after the single or combined removal of organs innervated by the splanchnic nerves. Removal of target organ(s) where the splanchnic nerves inhibit systemic inflammation should abolish any difference in LPS-induced plasma TNF-α levels between Sham and SplancX rats. Any secondary effects of extirpating organs should apply to both groups. Surprisingly, removal of the spleen and/or the adrenal glands did not prevent the reflex splanchnic anti-inflammatory action nor did the following removals: spleen + adrenals + intestine; spleen + intestine + stomach and pancreas; or spleen + intestine + stomach and pancreas + liver. Only when spleen, adrenals, intestine, stomach, pancreas, and liver were all removed did the difference between SplancX and Sham animals disappear. We conclude that the reflex anti-inflammatory action of the splanchnic nerves is distributed widely across abdominal organs.

The medial olivocochlear (MOC) efferent system modifies cochlear output to aid signal detection in noise, but the precise role of efferents in speech-in-noise understanding remains unclear. The current study examined the contribution of the MOC reflex for speech recognition in noise in 30 normal-hearing young adults (27 females, mean age = 22.7 yr). The MOC reflex was assessed using contralateral inhibition of transient-evoked otoacoustic emissions. Speech-in-noise perception was evaluated using the coordinate response measure presented in ipsilateral speech-shaped noise at signal-to-noise ratios (SNRs) ranging from -12 to 0 dB. Performance was assessed without and with the presence of contralateral noise to activate the MOC reflex. Performance was significantly better with contralateral noise only at the lowest SNR. There was a trend of better performance with increasing contralateral inhibition at the lowest SNR. Threshold of the psychometric function was significantly correlated with contralateral inhibition. Response time on the speech task was not significantly correlated with contralateral inhibition. Results suggest that the MOC reflex contributes to listening in low SNRs and the relationship between the MOC reflex and perception is highly dependent upon the task characteristics.

The aim of this study was to compare the differences in knee sensorimotor control between healthy men and women by measuring the joint position sense (JPS), sensation of muscle tension (steadiness), and onset of muscle activation (OMA).Twenty-four healthy women and 27 healthy men were tested. Knee sensorimotor control was assessed using the JPS test with electrogoniometers in 3 different ranges of motion, sensation of muscle tension using the isometric steadiness technique, and OMA against a mechanical perturbation. Each assessment was compared by sex, physical activity level, and right or left lower limb.The men obtained better values in the JPS test between 90º and 60º and between 30º and 0º than the women. The subjects with higher levels of physical activity also showed better values, between 90º and 60º and between 30º and 0º. The best results for steadiness were found in the women and the subjects with higher levels of physical activity. In the OMA test, no significant differences were found in the studied variables.The results suggest that higher levels of physical activity may determine better sensorimotor control. Men have better articular sensation, and women have better muscle strength control.O objetivo desse estudo foi comparar as diferenças no controle sensório-motor de joelho entre mulheres e homens saudáveis medindo o sensação da posição articular (SPA), Coeficiente de variações da força (Steadiness) e inicio ou ativação muscular (IAM).Foi avaliado 24 mulheres saudáveis e 27 homens saudáveis, realizando avaliações de SPA, o Sensação de tensão muscular (Steadiness) e o IAM, comparadas segundo sexo, nível de atividade física e extremidades inferiores direita ou esquerda.SPA: Os homens obtiveram melhores valores nessa prova entre 90-60° (p=0,0127) e em 30-0° (p=0,0017) ao comparado com as mulheres. as pessoas com maior nível de atividade física também se encontram melhores resultados entre 90-60° (p=0,0328) e 30-0° (p=0,0173). STEADINESS: Os melhores resultados foram para as mulheres em ambas extremidades (direita p=0,0002 e esquerda p=0,0009) e pessoas com maior nível de atividade física (direita p=0,0065 e esquerda p=0,0173). Para IAM não foi encontrado diferenças significativas nas variáveis estudadas.Os resultados sugerem que tanto maior nível de atividade física puderam determinar maior resultado no controle sensório-motor. Os homens tiveram maior sensação articular e as mulheres maior controle steadiness.

Neuropeptide Y (NPY) signaling via limbic NPY1 and 2 receptors (NPY1R and NPY2R, respectively) is known to modulate binge-like ethanol consumption in rodents. However, the role of NPY signaling in the medial prefrontal cortex (mPFC), which provides top-down modulation of the limbic system, is unknown. Here, we used "drinking-in-the-dark" (DID) procedures in C57BL/6J mice to address this gap in the literature. First, the impact of DID on NPY immunoreactivity (IR) was assessed in the mPFC. Next, the role of NPY1R and NPY2R signaling in the mPFC on ethanol consumption was evaluated through site-directed pharmacology. Chemogenetic inhibition of NPY1R+ neurons in the mPFC was performed to further evaluate the role of this population. To determine the potential role of NPY1R+ neurons projecting from the mPFC to the basolateral amygdala (BLA) this efferent population was selectively silenced. Three, 4-day cycles of DID reduced NPY IR in the mPFC. Intra-mPFC activation of NPY1R and antagonism of NPY2R resulted in decreased binge-like ethanol intake. Silencing of mPFC NPY1R+ neurons overall, and specifically NPY1R+ neurons projecting to the BLA, significantly reduced binge-like ethanol intake. We provide novel evidence that (1) binge-like ethanol intake reduces NPY levels in the mPFC; (2) activation of NPY1R or blockade of NPY2R reduces binge-like ethanol intake; and (3) chemogenetic inhibition of NPY1R+ neurons in the mPFC and NPY1R+ mPFC neurons projecting to the BLA blunts binge-like drinking. These observations provide the first direct evidence that NPY signaling in the mPFC modulates binge-like ethanol consumption.

To determine whether children aged 7 to 12 years with listening difficulties show objective evidence for efferent auditory function based on measurements of medial olivo-cochlear and middle ear muscle reflexes.Click-evoked otoacoustic emissions recorded with and without contralateral broadband noise and ipsilateral and contralateral tonal (1000, 2000 Hz) middle ear muscle reflex thresholds were examined.29 children diagnosed with suspected auditory processing disorder (APD) and a control group of 34 typically developing children participated in this study.Children with suspected APD had poorer performance on auditory processing tests than the control group. Middle ear muscle reflex thresholds were significantly higher at 2000 Hz in the suspected APD group for contralateral stimulation. MOC inhibition effects did not differ between APD and control groups.This research supports earlier studies showing altered acoustic reflexes in children with APD. No group differences were found for the MOC reflex measures, consistent with some earlier studies in children with APD.

Small fiber polyneuropathy is a well-recognized syndrome mitigated by somatic sensory afferent and autonomic efferent nerve fibers that respectively mediate pain, heat and cold temperature afferent and autonomic efferent function in the skin. A patient with low serum titers of neuronal acetylcholine receptor ganglionic antibodies and autonomic failure had symptomatic small fiber polyneuropathy late in life in the setting of autoimmune dementia and encephalopathy and prostate cancer. Large and small fiber polyneuropathy and dysautonomia were detected in routine electrodiagnostic and autonomic laboratory studies, and epidermal nerve fiber analysis of the calf and thigh. Clinical improvement for one year concomitant with intravenous immune globulin therapy preceded a clinical decline in neurocognitive function and death. Postmortem examination showed typical features of Alzheimer disease with neuropathic neuropathological changes in the peripheral nervous system, and viable autonomic ganglia consistent with a channelopathy mechanism involving postsynaptic neuronal nAChRs.

Chronic intermittent hypoxia (CIH), the main feature of obstructive sleep apnea (OSA), is associated with hypertension. The increased of carotid body (CB) sensitivity due to enhanced sympathetic efferent may be mainly responsible for the elevation of blood pressure. Accordingly, we studied this effect of Endothelin-1 (ET-1)-induced CB chemosensory response to CIH, as a vasoactive peptide expressed in CB. The purpose of this study was to investigate the mean arterial blood pressure (MAP) and renal sympathetic nerve activity (RSNA) responses in CIH group by injecting ET-1 to directly stimulate CB chemoreceptor. Furthermore, whether ET receptor-mediated PKC and p38MAPK signaling pathway was involved in CIH-induced CB activation was also studied. Male Sprague–Dawley rats were exposed to CIH (8 h/day for 3 weeks) and the MAP and RSNA were recorded in CIH rats and Sham rats. Our results demonstrated that ET-1-induced MAP and RSNA increase were mainly mediated by ETA receptor activation in CB chemosensory after CIH exposure. Moreover, P38MAPK and PKC signaling pathway might be involved in ET-1-induced increase of MAP and RSNA in CIH group, which provided a potential therapeutic target of OSA.

The search for the most potent strength training intervention is continuous. Maximal strength training (MST) yields large improvements in force-generating capacity (FGC), largely attributed to efferent neural drive enhancement. However, it remains elusive whether eccentric overload, before the concentric phase, may augment training-induced neuromuscular adaptations. A total of 53 23 ± 3 (SD)-yr-old untrained males were randomized to either a nontraining control group (CG) or one of two training groups performing leg press strength training with linear progression, three times per week for 8 wk. The first training group carried out MST with four sets of four repetitions at ~90% one-repetition maximum (1RM) in both action phases. The second group performed MST with an augmented eccentric load of 150% 1RM (eMST). Measurements were taken of 1RM and rate of force development (RFD), countermovement jump (CMJ) performance, and evoked potentials recordings [V-wave (V) and H-reflex (H) normalized to M-wave (M) in musculus soleus]. 1RM increased from 133 ± 16 to 157 ± 23 kg and 123 ± 18 to 149 ± 22 kg and CMJ by 2.3 ± 3.6 and 2.2 ± 3.7cm for MST and eMST, respectively (all P < 0.05). Early, late, and maximal RFD increased in both groups [634–1,501 N/s (MST); 644–2,111 N/s (eMST); P < 0.05]. These functional improvements were accompanied by increased V/M-ratio (MST: 0.34 ± 0.11 to 0.42 ± 14; eMST: .36 ± 0.14 to 0.43 ± 13; P < 0.05). Resting H/M-ratio remained unchanged. Training-induced improvements did not differ. All increases, except for CMJ, were different from the CG. MST is an enterprise for large gains in FGC and functional performance. Eccentric overload did not induce additional improvements, suggesting firing frequency and motor unit recruitment during MST may be maximal. NEW & NOTEWORTHY This is the first study to apply evoked potential recordings to investigate effects on efferent neural drive following high-intensity strength training with and without eccentric overload in a functionally relevant lower extremity exercise. We document that eccentric overload does not augment improvements in efferent neural drive or muscle force-generating capacity, suggesting that high-intensity concentric loads may maximally tax firing frequency and motor unit recruitment.